Analytical methods for aflatoxins in corn and peanuts.

Aflatoxin determinations can be approached many ways. Peanuts and corn are more often contaminated with aflatoxins B1 and B2 than with aflatoxins B1, B2, G1, and G2. Some countries are only interested in B1 content and others are interested in the total aflatoxin content. It is essential to safely handle all experimental materials associated with aflatoxin analyses or the aflatoxigenic fungi. Visual screening of suspect peanut lots, based on the presence of conidial heads of the Aspergillus flavus group, and screening corn for the presence of bright greenish yellow fluorescence (BGYF) are not chemical tests and such screening techniques may allow aflatoxin contaminated lots into commerce. Minicolumn screening procedures should always be used in conjunction with a quantitative method. Several thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) methods are suitable for quantitation and are in general use. Immunochemical methods such as the ELISA or affinity column methods are being rapidly developed. The chemical and immunochemical methods can be reliable if care is taken, using suitable controls and personnel that are well-trained. All analytical laboratories should stress safety and include suitable analytical validation procedures.